We're told the cause of death was a combination of complications from rheumatoid arthritis, acute ulcerative colitis, and pneumonia.

Frey had been battling intestinal issues for months and had surgery in November. We're told in the last few days his condition took a turn for the worse. He died in New York City.

Glenn co-wrote and sang on most of the Eagles hits, including "Take It Easy," "Tequila Sunrise," "Lyin' Eyes," and "Heartache Tonight," to name a few. He also co-wrote "Hotel California" and "Desperado" with Don Henley and took home 6 Grammys with the band.

A perfect day, the sun is sinking low
As evening falls the gentle breezes blow
The time we shared went by so fast
Just like a dream we knew it couldn't last

But I'd do it all again if I could somehow
But I must be leaving soon, it's your world now

It's your world now, my race is run
I'm moving on like the setting sun
No sad goodbyes, no tears allowed
You'll be alright, it's your world now

Even when we are apart
You'll always be in my heart
When dark clouds appear in the sky
Remember true love never dies

But first a kiss, one glass of wine
Just one more dance while there's still time
My one last wish, someday you'll see
How hard I tried and how much you meant to me

It's your world now, use well the time
Be part of something good, leave something good behind
The curtain falls, I take my bow
That's how it's meant to be, it's your world now
It's your world now, it's your world now